As a water-soluble polysaccharide, pullulan has been widely used in food processing, preservation and packaging of agricultural and marine products, and in the medical field. However, the lack of strong antioxidant activity of pullulan limits its application to some degree.. Therefore, in this study, ferulic acid-grafted-pullulan products with three different degrees of grafting were prepared using 4-dimethylaminopyridine (DMAP) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) as catalysts and pullulan and ferulic acid as raw materials. Proton nuclear magnetic resonance, Fourier transform infrared spectroscopy (FT-IR), ultraviolet (UV) spectroscopy, and thin-layer chromatography (TLC) were used to characterize the product structures. The results revealed that ferulic acid and pullulan were linked by ester bonds. Using pullulan as the control, the antioxidant activity of the complex was measured based on its scavenging abilities against 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), hydroxyl radical, and total reducing capacity. The results indicated that the scavenging abilities against various free radicals and reducing capacity of the complex were significantly increased, and that this enhancement was more significant as the degree of grafting increased, indicating that the coupling of two compounds can remarkably enhance the biochemical activity of pullulan.